Process for stabilizing trivalent phosphorus compounds with amines

ABSTRACT

The invention relates to a process for stabilizing a crystalline organic phosphite or phosphonite against hydrolysis, which comprises introducing a mixture comprising phosphite or phosphonite, a solvent or solvent mixture, and 0.1 to 100% by weight (relative to phosphite or phosphonite) of an amine and having a temperature of 50°-100° C. as a homogeneous melt into a liquid crystallization medium whose temperature during the addition is maintained 10°-70° C. below the temperature of the melt. 
     The phosphites or phosphonites stabilized according to the invention are distinguished by their excellent resistance to hydrolysis and have a long shelf life even at high atmospheric humidity. They can be advantageously used as stabilizers for organic material against the damaging effect of heat, oxygen, and/or light.

The invention relates to a process for increasing the shelf life oforganic phosphites and phosphonites and to an organic phosphite orphosphonite stabilized against hydrolysis.

Organic phosphites and phosphonites are widely used as heat stabilizersfor synthetic polymers. However, preparation, storage and use ofphosphites and phosphonites are rendered difficult by the fact thatthese compounds hydrolyze very easily. A particular problem is storageof the material at high atmospheric humidity.

Various methods have been proposed for arriving at products havingimproved stability to hydrolysis; these include, apart from preparationprocesses leading to purer products and methods for purifying theready-to-use compounds, in particular the addition of specificstabilizers which, on the one hand, reduce the tendency to hydrolysisand, on the other hand, do not result in adverse effects during thelater use of the compounds.

EP-A-278 579 proposes to use a hydrolytically stable stabilizer mixturein which the crystalline phosphite is embedded in an amorphous phenolicantioxidant. This stabilizer mixture is obtainable by rapid cooling of amelt of both compounds or of a suspension consisting of crystallinephosphite and liquid phenol derivatives.

The addition of amines as stabilizers against hydrolysis is described,for example, in U.S. Pat. No. 3,553,298. Further publications regardingthe stabilizing of phosphites with amines are U.S. Pat. No. 3,787,537,EP-A-168 721 and EP-A-167 969. The recommended compounds are inparticular tertiary alkanolamines and alkylamines, pyridines andanilines; typical examples are triethylamine, diethanolamine,triethanolamine, di- and triisopropanolamine (TIPA),tetraisopropanolethylenediamine, aniline, phenylenediamine andhexamethylenetetramine. In general, the amines are used in amounts of upto about 5% by weight (relative to the phosphite to be stabilized);incorporation of the amine is effected by dry milling or by dissolutionin or mixing with the phosphite melt, followed by crystallization.

Despite the known stabilization methods listed here, there is a need forfurther improvement of the hydrolytic stability of organic phosphitesand phosphonites.

It has now been found that the stabilizing effect of amines cansurprisingly be increased by applying the amine in a special process.

Accordingly, the invention provides a process for stabilizing acrystalline organic phosphite or phosphonite against hydrolysis, whichcomprises introducing a mixture comprising phosphite or phosphonite, asolvent or solvent mixture, and 0.1 to 100% by weight (relative to thephosphite or phosphonite) of an amine and having a temperature of50°-100° C. as a homogeneous melt into a liquid crystallization mediumwhose temperature during the addition is maintained 10°-70° C. below thetemperature of the melt.

The melt is the liquid mixture comprising amine, solvent and thephosphite or phosphonite to be stabilized. The melt can contain a smallor a large amount of solvent, for example 20 or 500% by weight (relativeto the phosphite or phosphonite) and thus can also be more like asolution. The important feature is that the melt is homogeneous, i.e.that none of the components mentioned are crystalline any more andseparation into 2 or more liquid phases does not take place. The amineused can be an individual compound or a mixture of compounds.

In principle, any organic compounds or mixtures of compounds which areliquid in the temperature range from 10° to 60° C. under atmosphericpressure, do not cause solvolysis and are capable of dissolving asufficient amount of solid phosphite or phosphonite above 50° C., insome cases up to 100° C., or are sufficiently miscible with the meltedphosphite or phosphonite, can be used as the solvent. For example,sufficient solubility or miscibility is given if the homogeneous liquidmixture can contain up to 15, in particular up to 50, % by weight ofphosphite or phosphonite. Examples of suitable solvents are alcohols orhydrocarbons or mixtures thereof.

Advantageously one compound or a mixture of two compounds is used as thesolvent in the melt. The main solvent is used in an amount of 20 to 500%by weight, relative to the phosphite or phosphonite, and the furthersolvent in an amount of 0-50% by weight, relative to the main solvent.The melt preferably contains an alcohol or a hydrocarbon as the mainsolvent in an amount of 20 to 500% by weight, relative to the phosphiteor phosphonite, and a further solvent in an amount of 0-50, inparticular 0-20, % by weight, relative to the main solvent. It is alsopossible to use a mixture of alcohols or a mixture of hydrocarbons.

Examples of suitable alcohols are lower alcohols, such as C₁ -C₅alkanols, in particular C₁ -C₃ alkanols, such as methanol, ethanol,propanol or isopropanol. Isopropanol and methanol are particularlysuitable.

Examples of suitable hydrocarbons are C₆ -C₁₃ alkanes, cycloalkanes oralkylated cycloalkanes having 6 to 12 carbon atoms, benzene, oralkylaromatics having 6 to 10 atoms; toluene, ligroin, petroleum ether,xylene, and in particular toluene are particularly suitable.

Frequently the further solvent used is a hydrocarbon or a mixture ofhydrocarbons in the case where the main solvent is an alcohol, or analcohol in the case where the main solvent is a hydrocarbon. Suitablealcohols and hydrocarbons are the ones listed above.

The organic phosphites or phosphonites usable according to the inventionare solid at 20° C.; in general they are crystalline solids.

Phosphites are here understood to mean organic phosphites of the formulaP(OR)₃ in which the radicals R are hydrocarbon radicals, which maycontain hetero atoms, and moreover a maximum of two of the threeradicals R can be hydrogen atoms. Hetero atoms are any atoms with theexception of carbon and hydrogen, in particular the atoms N, O, F, Si,P, S, Cl, Br, Sn and I.

Phosphonites are esters of phosphonous acid of the formula P(OR)₂ R inwhich R is as defined above or can be halogen.

In the process according to the invention, crude phosphite or crudephosphonite solutions such as are obtained during preparation beforecrystallization can be used.

The product of the process according to the invention is a mixture ofcompounds comprising solid phosphite or phosphonite and amine.

The temperature of the melt is preferably 55°-90° C., in particular60°-80° C.

In the process according to the invention, the difference in temperaturebetween melt and crystallization medium is advantageously at least 20°C., for example 30°-70° C., in particular 40°-60° C.

The crystallization medium is preferably maintained at a temperaturebeing at least 10° C., for example 10°-60° C., below the resultingtemperature of the liquidus. The temperature of the crystallizationmedium is preferably 20°-60° C. below the resulting temperature of theliquidus.

The resulting temperature of the liquidus is the temperature at which ahomogeneous phase formed from the melt and crystallization medium is inthermodynamic equilibrium with phosphite crystals; below thistemperature, crystallization starts, and above the mixture forms ahomogeneous melt. In practice, this temperature is advantageouslydetermined by mixing tests, for example by means of calorimetric (forexample by DSC) and/or optical methods.

Advantageously, 80-800% by weight, in particular 10-500% by weight, oforganic solvent, relative to the phosphite or phosphonite in the melt,is used as the crystallization medium.

Advantageously, alcohols are used as the crystallization medium; thus,for example, a C₁ -C₅ alkanol or a mixture of various C₁ -C₅ alkanols isused. C₁ -C₃ Alkanols, such as methanol, ethanol, propanol orisopropanol, are preferably used as the crystallization medium.

Advantageously, seed crystals are added to the crystallization medium.Accordingly, the crystallization medium preferably consists of asuspension of 2 to 20% by weight of crystalline phosphite orphosphonite, relative to the phosphite or phosphonite in the melt.Moreover, it is advantageous for the crystallization medium to be50-100% saturated with the amine, 100% of saturation corresponding to anamine concentration at which dissolved and solid amine can be presentside by side.

In general, the melt contains 0.1 to 50% by weight of amine, relative tothe phosphite or phosphonite; preferably 0.2 to 25% by weight, inparticular 0.5 to 20% by weight, in particular 1 to 10% by weight, areused (relative to the phosphite or phosphonite in the melt).

During the metered addition of the melt, the crystallization medium isadvantageously stirred. After both mixtures have been combined, furtherworkup can take place in a manner known per se, for example by coolingto 10°-15° C. and isolation of the crystalline product.

The stabilized phosphite or phosphonite is generally obtained as apowder in which the amine is homogeneously distributed. Typically itcontains 0.01 to 20, in particular 0.05 to 10, in particular 0.1 to 5, %by weight of amine (relative to the phosphite or phosphonite).

The amine used in the process according to the invention is preferably asterically hindered amine or one of the formula I ##STR1## in which X¹and X², independently of one another, are H, C₁ -C₂ alkyl, C₄ -C₂₀ alkylwhich is interrupted by one or more --O-- and unsubstituted orsubstituted by one or more hydroxyl groups, or is C₂ -C₂₀ hydroxyalkyl,and X³ is C₂ -C₂₀ alkyl, C₄ -C₂₀ alkyl which is interrupted by one ormore --O-- and unsubstituted or substituted by one or more hydroxylgroups, or is --(CH₂)_(m) --NX¹ X², or C₂ -C₂₀ hydroxyalkyl, or in whichX² and X³ together are --(CH₂)_(m) --, --C₂ H₄ --O--C₂ H₄ -- or --C₂ H₄--NX¹ --C₂ H₄ --, m being an integer from the range 4 to 6 and X¹ and X²being as defined above.

The sterically hindered amine is in general a cyclic sterically hinderedamine, in particular a compound from the series of polyalkylpiperidineor -piperazine derivatives containing a group of the formulae II or III##STR2## in which G is hydrogen or methyl, and G₁ and G₂ are hydrogen,methyl or together are ═O; preferably, the polyalkylpiperidine group ofthe formula II or III are substituted in the 4 position by one or twopolar substituents or a polar spiro ring system.

X¹, X² and X³ are, for example, independently of one another, ethyl,propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, hydroxyethyl,hydroxypropyl, hydroxybutyl, hydroxypentyl, hydroxyhexyl, hydroxyheptyl,hydroxyoctyl, hydroxynonyl or hydroxydecyl.

Preferably, X¹, X² and X³ are identical.

The amine of the formula I is preferably a tertiary amine, particularlypreferably a tri-C₂ -C₄ alkanolamine, in particular triisopropanolamine(=amine A).

Of importance is a process in which the amine used is a tertiary amineof the formula I or a cyclic sterically hindered amine containing atleast one group of the formulae II or III in which G is hydrogen, and G¹and G² are hydrogen or together are a substituent ═O.

Particularly advantageously, derivatives of2,2,6,6-tetramethylpiperidine are used in the process according to theinvention.

Of importance is in particular the use of the classes ofpolyalkylpiperidines described below under (a) to (h), which carry agroup of the formula II or III as mentioned above:

(a) compounds of the formula IV ##STR3## in which n is a number from 1to 4, G and G¹, independently of one another, are hydrogen or methyl,

G¹¹ is hydrogen, oxyl, hydroxyl, C₁ -C₁₈ alkyl, C₃ -C₈ alkenyl, C₃ -C₈alkynyl, C₇ -C₁₂ aralkyl, C₁ -C₁₈ alkoxy, C₅ -C₈ cycloalkoxy, C₇ -C₉phenylalkoxy, C₁ -C₈ alkanoyl, C₃ -C₅ alkenoyl, C₁ -C₁₈ alkanoyloxy,benzyloxy, glycidyl or a group --CH₂ CH(OH)--Z, in which Z is hydrogen,methyl or phenyl, G¹¹ being preferably H, C₁ -C₄ alkyl, allyl, benzyl,acetyl or acryloyl and

G¹² being, in the case where n is 1, hydrogen, C₁ -C₁₈ alkyl which maybe interrupted by one or more oxygen atoms, cyanoethyl, benzyl,glycidyl, a monovalent radical of an aliphatic, cycloaliphatic,araliphatic, unsaturated or aromatic carboxylic acid, carbamic acid orphosphorus-containing acid or a monovalent silyl radical, preferably aradical of an aliphatic carboxylic acid having 2 to 18 C atoms, acycloaliphatic carboxylic acid having 7 to 15 C atoms, anα,β-unsaturated carboxylic acid having 3 to 5 C atoms or an aromaticcarboxylic acid having 7 to 15 C atoms it being possible for thecarboxylic acid to be substituted in each case in the aliphatic,cycloaliphatic or aromatic portion by 1 to 3 groups --COOZ¹², in whichZ¹² is H, C₁ -C₂₀ alkyl, C₃ -C₁₂ alkenyl, C₅ -C₇ cycloalkyl, phenyl orbenzyl,

in the case where n is 2, C₂ -C₁₂ alkylene, C₄ -C₁₂ alkenylene,xylylene, a divalent radical of an aliphatic, cycloaliphatic,araliphatic or aromatic dicarboxylic acid, dicarbamic acid orphosphorus-containing acid, or a divalent silyl radical, preferably aradical of an aliphatic dicarboxylic acid having 2 to 36 C atoms, acycloaliphatic or aromatic dicarboxylic acid having 8-14 C atoms, or analiphatic, cycloaliphatic or aromatic dicarbamic acid having 8-14 Catoms, it being possible for the dicarboxylic acid to be substituted ineach case in the aliphatic, cycloaliphatic or aromatic portion by 1 or 2groups --COOZ¹²,

in the case where n is 3, a trivalent radical of an aliphatic,cycloaliphatic or aromatic tricarboxylic acid, which may be substitutedin the aliphatic, cycloaliphatic or aromatic portion by --COOZ¹², anaromatic tricarbamic acid or a phosphorus-containing acid, or atrivalent silyl radical, and

in the case where n is 4, a tetravalent radical of an aliphatic,cycloaliphatic or aromatic tetracarboxylic acid.

The carboxylic acid radicals mentioned include in each case radicals ofthe formula (--CO)_(n) R, the meaning of n being given above and themeaning of R being apparent from the definition given.

Examples of C₁ -C₁₂ alkyl substituents, if present, are methyl, ethyl,n-propyl, n-butyl, sec-butyl, tert-butyl, n-hexyl, n-octyl,2-ethylhexyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl.

Examples of G¹¹ or G¹² as C₁ -C₁₈ alkyl can be the abovementioned groupsand in addition, for example, n-tridecyl, n-tetradecyl, n-hexadecyl orn-octadecyl.

Examples of G¹¹ as C₃ -C₈ alkenyl can be 1-propenyol, allyl, methallyl,2-butenyl, 2-pentenyl, 2-hexenyl, 2-octenyl, 4-tert-butyl-2-butenyl.

G¹¹ as C₃ -C₈ alkynyl is preferably propargyl.

G¹¹ as C₇ -C₁₂ aralkyl is in particular phenethyl and especially benzyl.

Examples of G¹¹ as C₁ -C₈ alkanoyl are formyl, propionyl, butyryl,octanoyl, but preferably acetyl and as C₃ -C₅ alkenoyl in particularacryloyl.

G¹² as a monovalent radical of a carboxylic acid is, for example, anacetic acid, caproic acid, stearic acid, acrylic acid, methacrylic acid,benzoic acid or β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acidradical.

G¹² as a monovalent silyl radical is, for example, a radical of theformula --(C_(j) H_(2j))--Si(Z')₂ Z", in which j is an integer from therange 2 to 5, and Z' and Z", independently of one another, are C₁ -C₄alkyl or C₁ -C₄ alkoxy.

G¹² as a divalent radical of a dicarboxylic acid is, for example, amalonic acid, succinic acid, glutaric acid, adipic acid, suberic acid,sebacic acid, maleic acid, itaconic acid, phthalic acid, dibutylmalonicacid, dibenzylmalonic acid,butyl(3,5-di-tert-butyl-4-hydroxybenzyl)malonic acid orbicycloheptenedicarboxylic acid radical.

G¹² as a trivalent radical of a tricarboxylic acid is, for example, atrimellitic acid, citric acid or nitrilotriacetic acid radical.

G¹² as a tetravalent radical of a tetracarboxylic acid is, for example,the tetravalent radical of butane-1,2,3,4-tetracarboxylic acid or ofpyromellitic acid.

G¹² as a divalent radical of a dicarbamic acid is, for example, ahexamethylenedicarbamic acid or a 2,4-toluylenedicarbamic acid radical.

Preference is given to compounds of the formula IV in which G ishydrogen, G¹¹ is hydrogen or methyl, n is 2, and G¹² is the diacylradical of an aliphatic dicarboxylic acid having 4-12 C atoms.

Examples of polyalkylpiperidine compounds from this class are thefollowing compounds:

1) 4-hydroxy-2,2,6,6-tetramethylpiperidine

2) 1-allyl-4-hydroxy-2,2,6,6-tetramethylpiperidine

3) 1-benzyl-4-hydroxy-2,2,6,6-tetramethylpiperidine

4) 1-(4-tert-butyl-2-butenyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine

5) 4-stearoyloxy-2,2,6,6-tetramethylpiperidine

6) 1-ethyl-4-salicyloyloxy-2,2,6,6-tetramethylpiperidine

7) 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine

8) 1,2,2,6,6-pentamethylpiperidin-4-ylβ-(3,6-di-tert-butyl-4-hydroxyphenyl)propionate

9) di(1-benzyl-2,2,6,6-tetramethylpiperidin-4-yl)maleate

10) di(2,2,6,6-tetramethylpiperidin-4-yl) succinate

11) di(2,2,6,6-tetramethylpiperidin-4-yl) glutarate

12) di(2,2,6,6-tetramethylpiperidin-4-yl) adipate

13) di(2,2,6,6-tetramethylpiperidin-4-yl) sebacate

14) di(1,2,2,6,6-pentamethylpiperidin-4-yl) sebacate

15) di(1,2,3,6-tetramethyl-2,6-diethyl-piperidin-4-yl) sebacate

16) di(1-allyl-2,2,6,6-tetramethylpiperidin-4-yl) phthalate

17) 1-hydroxy-4-β-cyanoethyloxy-2,2,6,6-tetramethylpiperidine

18) 1-acetyl-2,2,6,6-tetramethylpiperidin-4-yl acetate

19) trimellitic acid tri-(2,2,6,6-tetramethylpiperidin-4-yl) ester

20) 1-acryloyl-4-benzyloxy-2,2,6,6-tetramethylpiperidine

21) di(2,2,6,6-tetramethylpiperidin-4-yl) diethylmalonate

22) di-(1,2,2,6,6-pentamethylpiperidin-4-yl) dibutylmalonate

23) di(1,2,2,6,6-pentamethylpiperidin-4-yl)butyl(3,5-di-tert-butyl-4-hydroxybenzyl)malonate

24) di(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate

25) di(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate

26)hexane-1',6'-bis(4-carbamoyloxy-1-n-butyl-2,2,6,6-tetramethyl-piperidine)

27)toluene-2',4'-bis(4-carbamoyloxy-1-n-propyl-2,2,6,6-tetramethyl-piperidine)

28) dimethylbis(2,2,6,6-tetramethylpiperidine-4-oxy)silane

29) phenyltris(2,2,6,6-tetramethylpiperidin-4-oxy)silane

30) tris(1-propyl-2,2,6,6-tetramethylpiperidin-4-yl) phosphite

31) tris(1-propyl-2,2,6,6-tetramethylpiperidin-4-yl) phosphite

32) bis-(1,2,2,6,6-pentamethylpiperidin-4-yl) phenylphosphonate

33) 4-hydroxy-1,2,2,6,6-pentamethylpiperidine

34) 4-hydroxy-N-hydroxyethyl-2,2,6,6-tetramethylpiperidine

35) 4-hydroxy-N-(2-hydroxypropyl)-2,2,6,6-tetramethylpiperidine

36) 1-glycidyl-4-hydroxy-2,2,6,6-tetramethylpiperidine

(b) compounds of the formula (V) ##STR4## in which n is 1 or 2, G, G¹and G¹¹ have the meaning given under (a), G¹³ is hydrogen, C₁ -C₁₂alkyl, C₂ -C₅ aydroxyalkyl, C₅ -C₇ cycloalkyl, C₇ -C₈ aralkyl, C₂ -C₁₈alkanoyl, C₃ -C₅ alkenoyl, benzoyl or a group of the formula ##STR5##and

G¹⁴ is, in the case where n is 1, hydrogen, C₁ -C₁₈ alkyl, C₃ -C₈alkenyl, C₅ -C₇ cycloalkyl, C₁ -C₄ alkyl which is substituted by ahydroxyl, cyano, alkoxycarbonyl or carbamide group, or is glycidyl, agroup of the formula --CH₂ --CH(OH)--Z or of the formula --CONH--Z, inwhich Z is hydrogen, methyl or phenyl;

in the case where n is 2, C₂ -C₁₂ alkylene, C₆ -C₁₂ arylene, xylylene, a--CH₂ --CH(OH)--CH₂ -- group or a group --CH₂ --CH(OH)--CH₂ --O--D--O--,in which D is C₂ -C₁₀ alkylene, C₆ -C₁₅ arylene, C₆ -C₁₂ cycloalkylene,or, provided G¹³ is not alkanoyl, alkenoyl or benzoyl, G¹⁴ can also be1-oxo-C₂ -C₁₂ alkylene, a divalent radical of an aliphatic,cycloaliphatic or aromatic dicarboxylic acid or dicarbamic acid or elsethe group --CO--, or, in the case where n is 1, G¹³ and G¹⁴ together canbe the divalent radical of an aliphatic, cycloaliphatic or aromatic 1,2-or 1,3-dicarboxylic acid.

C₁ -C₁₂ Alkyl or C₁ -C₁₈ alkyl substituents, if present, have themeaning already given under (a).

C₅ -C₇ Cycloalkyl substituents, if present, are in particularcyclohexyl.

G¹³ as C₇ -C₈ aralkyl is in particular phenylethyl or especially benzyl.G¹³ as C₂ -C₅ hydroxyalkyl is in particular 2-hydroxyethyl or2-hydroxypropyl.

Examples of G¹³ as C₂ -C₁₈ alkanoyl are propionyl, butyryl, octanoyl,dodecanoyl, hexadecanoyl, octadecanoyl, but preferably acetyl and, as C₃-C₅ alkenoyl, in particular acryloyl.

Examples of G¹⁴ as C₂ -C₈ alkenyl are allyl, methallyl, 2-butenyl,2-pentenyl, 2-hexenyl or 2-octenyl.

Examples of G¹⁴ as C₁ -C₄ alkyl which is substituted by a hydroxyl,cyano, alkoxycarbonyl or carbamic group can be 2-hydroxyethyl,2-hydroxypropyl, 2-cyanoethyl, methoxycarbonylmethyl,2-ethoxycarbonylethyl, 2-aminocarbonylpropyl or2-(dimethylaminocarbonyl)ethyl.

Examples of C₂ -C₁₂ alkylene substituents, if present, are ethylene,propylene, 2,2-dimethylpropylene, tetramethylene, hexamethylene,octamethylene, decamethylene or dodecamethylen.

Examples of C₆ -C₁₅ arylene substituents, if present are o-, m- orp-phenylene, 1,4-naphthylene or 4,4'-diphenylene.

A C₆ -C₁₂ cycloalkylene is in particular cyclohexylene.

Preference is given to compounds of the formula V in which n is 1 or 2,G is hydrogen. G¹¹ is hydrogen or methyl, G¹³ is hydrogen, C₁ -C₁₂ alkylor a group of the formula ##STR6## and G¹⁴ is hydrogen or C₁ -C₁₂ alkylin the case where n=1 and C₂ -C₈ alkylene or 1-oxo-C₂ -C₈ alkylene inthe case where n is 2.

Examples of polyalkylpiperidine compounds of this class are thefollowing compounds:

37) N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylene-1,6-diamine

38)N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylene-1,6-diacetamide

39) bis(2,2,6,6-tetramethylpiperidin-4-yl)amine

40) 4-benzoylamino-2,2,6,6-tetramethylpiperidine

41) N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)-N,N'-dibutyladipamide

42)N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)-N,N'-dicyclohexyl-2-hydroxypropylene-1,3-diamine

43) N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)-p-xylylene diamine

44) N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)succinediamide

45) di(2,2,6,6-tetramethylpiperidin-4-yl)N-(2,2,6,6-tetramethylpiperidin-4-yl)-β-aminodipropionate

46) the compound of the formula ##STR7## 47)4-[bis(2-hydroxyethyl)amino]-1,2,2,6,6-pentamethylpiperidine 48)4-(3-methyl-4-hydroxy-5-tert-butylbenzamido)-2,2,6,6-tetramethylpiperidine

49) 4-methacrylamido-1,2,2,6,6-pentamethylpiperidine

(c) compounds of the formula (VI) ##STR8## in which n is 1 or 2, G, G¹and G¹¹ have the meaning given under (a), and G¹⁵ is C₂ -C₈ alkylene or-hydroxyalkylene or C₄ -C₂₂ acyloxyalkylene, in the case where n is 1,and is the group (--CH₂)₂ C(CH₂ --)₂, in the case where n is 2.

Examples of G¹⁵ as C₂ -C₈ alkylene or -hydroxyalkylene are ethylene,1-methylethylene, propylene, 2-ethylpropylene or2-ethyl-2-hydroxymethylpropylene.

G¹⁵ as C₄ -C₂₂ acyloxyalkylene is, for example,2-ethyl-2-acetoxymethylpropylene.

Examples of polyalkylpiperidine of this class are the followingcompounds:

50) 9-aza-8,8,10,10-tetramethyl-1,5-dioxaspiro[5.5]undecane

51) 9-aza-8,8,10,10-tetramethyl-3-ethyl-1,5-dioxaspiro[5.5]undecane

52) 8-aza-2,7,7,8,9,9-hexamethyl-1,4-dioxaspiro[4.5]decane

53)9-aza-3-hydroxymethyl-3-ethyl-8,8,9,10,10-pentamethyl-1,5-dioxaspiro[5.5]undecane

54)9-aza-3-ethyl-3-acetoxymethyl-9-acetyl-8,8,10,10-tetramethyl-1,5-dioxaspiro[5.5]undecane

55)2,2,6,6-tetramethylpiperidine-4-spiro-2'-(1',3'-dioxane)-5'-spiro-5"-(1",3"-dioxane)-2"-spiro-4"'-(2"',2'",6"',6"'-tetramethylpiperidine).

(d) Compounds of the formulae VIIA, VIIB and VIIC, preference beinggiven to compounds of the formula VIIC ##STR9## in which n is 1 or 2, G,G¹ and G¹¹ have the meaning given under (a), G¹⁶ is hydrogen, C₁ -C₁₂alkyl, allyl, benzyl, glycidyl or C₂ -C₆ alkoxyalkyl and G¹⁷ is, in thecase where n is 1, hydrogen, C₁ -C₁₂ alkyl, C₃ -C₅ alkenyl, C₇ -C₉aralkyl, C₅ -C₇ cycloalkyl, C₂ -C₄ hydroxyalkyl, C₂ -C₆ alkoxyalkyl, C₆-C₁₀ aryl, glycidyl or a group of the formula --(CH₂)p--COO--Q or of theformula --(CH₂)p--O--CO--Q, in which p is 1 or 2 and Q is C₁ -C₄ alkylor phenyl, and, in the case where n is 2, C₂ -C₁₂ alkylene, C₄ -C₁₂alkenylene, C₆ -C₁₂ arylene, a group --CH₂ --CH(OH)--CH₂ --O--D--O--CH₂--CH(OH)--CH₂ -- , in which D is C₂ -C₁₀ alkylene, C₆ -C₁₅ arylene, C₆-C₁₂ cycloalkylene, or a group --CH₂ CH(OZ')CH₂ --(OCH₂ --CH(OZ')CH₂)₂--, in which Z' is hydrogen, C₁ -C₁₈ alkyl, allyl, benzyl, C₂ -C₁₂alkanoyl or benzoyl, T₁ and T₂, independently of one another, arehydrogen, C₁ -C₁₈ alkyl or unsubstituted or halogen- or C₁ -C₄alkyl-substituted C₆ -C₁₀ aryl or C₇ -C₉ aralkyl, or T₁ and T₂ togetherwith the C atom linking them form a C₅ -C₁₄ cycloalkane ring.

Examples of C₁ -C₁₂ alkyl substituents, if present, are methyl, ethyl,n-propyl, n-butyl, sec-butyl, tert-butyl, n-hexyl, n-octyl,2-ethylhexyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl.

Examples of C₁ -C₁₈ alkyl substituents, if present, can be theabovementioned groups and in addition, for example, n-tridecyl,n-tetradecyl, n-hexadecyl or n-octadecyl.

Examples of C₂ -C₆ alkoxyalkyl substituents, if present, aremethoxymethyl, ethoxymethyl, propoxymethyl, tert-butoxymethyl,ethoxyethyl, ethoxypropyl, n-butoxyethyl, tert-butoxyethyl,isopropoxyethyl or propoxypropyl.

Examples of G¹⁷ as C₃ -C₅ alkenyl are 1-propenyl, allyl, methallyl,2-butenyl or 2-pentenyl.

G¹⁷, T₁ and T₂ as C₇ -C₉ aralkyl are in particular phenethyl orespecially benzyl. A cycloalkane ring formed by T₁ and T₂ together withthe C atom can be, for example, a cyclopentane, cyclohexane, cyclooctaneor cyclododecane ring.

Examples of G¹⁷ as C₂ -C₄ hydroxyalkyl are 2-hydroxyethyl,2-hydroxypropyl, 2-hydroxybutyl or 4-hydroxybutyl.

G¹⁷, T₁ and T₂ as C₆ -C₁₀ aryl are in particular phenyl, α- orβ-naphthyl, which are unsubstituted or substituted by halogen or C₁ -C₄alkyl.

Examples of G¹⁷ as C₂ -C₁₂ alkylene are ethylene, propylene,2,2-dimethylpropylene, tetramethylene, hexamethylene, octamethylene,decamethylene or dodecamethylene.

G¹⁷ as C₄ -C₁₂ alkenylene is in particular 2-butenylene, 2-pentenyleneor 3-hexenylene.

Examples of G¹⁷ as C₆ -C₁₂ arylene are o-, m- or p-phenylene,1,4-naphthylene or 4,4'-diphenylene.

Examples of Z' as C₂ -C₁₂ alkanoyl are propionyl, butyryl, octanoyl,dodecanoyl, but preferably acetyl.

D as C₂ -C₁₀ alkylene, C₆ -C₁₅ arylene or C₆ -C₁₂ cycloalkylene is asdefined under (b).

Examples of polyalkylpiperidine compounds of this class are thefollowing compounds:

56) 3-benzyl-1,3,8-triaza-7,7,9,9-tetramethylspiro[4.5]decane-2,4-dione

57) 3-n-octyl-1,3,8-triaza-7,7,9,9-tetramethylspiro[4.5]decane-2,4-dione

58) 3-allyl-1,3,8-triaza-1,7,7,9,9-pentamethylspiro[4.5]decane-2,4-dione

59)3-glycidyl-1,3,8-triaza-7,7,8,9,9-pentamethylspiro[4.5]decane-2,4-dione

60) 1,3,7,7,8,9,9-heptamethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione

61)2-isopropyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxospiro-[4.5]decane

62)2,2-dibutyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxospiro-[4.5]-decane

63)2,2,4,4-tetramethyl-7-oxa-3,20-diaza-21-oxodispiro[5.1.11.2]-heneicosane

64) 2-butyl-7,7,9,9-tetramethyl-1-oxa-4,8-diaza-3-oxospiro[4.5]decane

and preferably:

65)8-acetyl-3-dodecyl-1,3,8-triaza-7,7,9,9-tetramethylspiro[4.5]-decane-2,4-dione

or the compounds of the following formulae: ##STR10##

(e) Compounds of the formula VIII, which on their part are preferred,##STR11## in which n is 1 or 2 and G¹⁸ is a group of one of the formulae##STR12## in which G and G¹¹ are as defined under (a) and G¹ and G² arehydrogen, methyl or together are a substituent ═O,

E is --O-- or --NG¹³ --,

A is C₂ -C₆ alkylene or --(CH₂)₃ --O-- and

x is 0 or 1,

G¹³ is hydrogen, C₁ -C₁₂ alkyl, C₂ -C₅ hydroxyalkyl or C₅ -C₇cycloalkyl,

G¹⁹ is identical to G¹⁸ or one of the groups --NG²¹ G²², --OG²³, --NHCH₂OG²³ or --N(CH₂ OG²³)₂,

G²⁰ is identical to G¹⁸ or G¹⁹ in the case where n is 1, and is a group--E--B--E--, in which B is C₂ -C₈ alkylene or C₂ -C₈ alkylene which isinterrupted by 1 or 2 --N(G²¹)-- groups in the case where n is 2,

G²¹ is C₁ -C₁₂ alkyl, cyclohexyl, benzyl, C₁ -C₄ hydroxyalkyl or a groupof the formula ##STR13##

G²² is C₁ -C₁₂ alkyl, cyclohexyl, benzyl, C₁ -C₄ hydroxyalkyl, and

G²³ is hydrogen, C₁ -C₁₂ alkyl or phenyl, or G²¹ and G²² together are C₄-C₅ alkylene or -oxaalkylene, for example ##STR14## or a group of theformula ##STR15## or G²¹ is a group of the formula ##STR16##

Any C₁ -C₁₂ alkyl substituents present are, for example, methyl, ethyl,n-propyl, n-butyl, sec-butyl, tert-butyl, n-hexyl, n-octyl,2-ethylhexyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl.

Any C₁ -C₄ hydroxyalkyl substituents present are, for example,2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, 2-hydroxybutyl or4-hydroxybutyl.

Examples of A as C₂ -C₆ alkylene are ethylene, propylene,2,2-dimethylpropylene, tetramethylene or hexamethylene.

Examples of G²¹ and G²² together as C₄ -C₅ alkylene or oxaalkylene aretetramethylene, pentamethylene or 3-oxapentamethylene.

Examples of polyalkylpiperidine compounds of this class are thecompounds of the following formulae: ##STR17##

(f) oligomers or polymer compounds whose recurring structural unitcontains a 2,2,6,6-tetraalkylpiperidine radical of the formula III, inparticular polyesters, polyethers, polyamides, polyamines,polyurethanes, polyureas, polyaminotriazines, poly(meth)acrylates,poly(meth)acrylamides and copolymers thereof containing such radicals.

Examples of 2,2,6,6-polyalkylpiperidine light stabilizers of this classare the compounds of the following formulae, m being a number from 2 toabout 200. ##STR18##

R being ##STR19## or a branching of the chain ##STR20## m' and m" areeach an integer from the range 0-200 on condition that m'+m" is m.

Further examples of polymer light stabilizers are reaction products ofcompounds of the formula ##STR21## with epichlorohydrin;

polyesters obtained by reaction of butane-1,2,3,4-tetracarboxylic acidwith a bifunctional alcohol of the formula ##STR22##

the carboxyl side chains of which originating from the tetracarboxylicacid have been esterified with 2,2,6,6-tetramethyl-4-hydroxypiperidine;

compounds of the formula ##STR23## in which about one third of theradicals R are --C₂ H₅ and the others are ##STR24## and m is a numberfrom the range 2 to 200; or

copolymers whose recurring unit is composed of 2 units ##STR25## and 1unit each of ##STR26##

(g) Compounds of the formula IX ##STR27## in which G, G¹ and G¹¹ are asdefined under (a).

Preference is given to compounds of the formula IX in which G ishydrogen or methyl and G¹¹ is hydrogen or methyl.

Examples of such compounds are:

96) 2,2,6,6-tetramethyl-4-piperidone (triacetoneamine)

97) 1,2,2,6,6-pentamethyl-4-piperidone

98) 2,2,6,6-tetramethyl-4-piperidone 1-oxide

99) 2,3,6-trimethyl-2,6-diethyl-4-piperidone

(h) compounds of the formula X ##STR28## in which n is 1 or 2 and inwhich G and G¹¹ are as defined under (a) and G¹⁴ is as defined under(b), the meanings --CONH--Z and --CH₂ --CH(OH)--CH₂ --O--D--O-- beingexcluded for G¹⁴.

Examples of such compounds are: ##STR29##

The following amines are particularly preferred for use in the processaccording to the invention:

Compounds of the formula IV in which n is an integer from the range 1 to4, G and G¹ are hydrogen, and

G¹¹ is hydrogen or C₁ -C₁₈ alkyl, and

G¹², in the case where n is 1, is a radical of the formula --(C_(j)H_(2j))--Si(Z')₂ Z", in which j is an integer from the range 2 to 5 andZ' and Z", independently of one another, are C₁ -C₄ alkyl or C₁ -C₄alkoxy, and

G¹², in the case where n is 2, is a radical of an aliphatic dicarboxylicacid having 2 to 12 C atoms which may be substituted by --COOZ¹², Z¹²being C₁ -C₂₀ alkyl,

G¹², in the case where n is 3, is a radical of an aromatic tricarboxylicacid having 9 to 15 C atoms,

G¹², in the case where n is 4, is a radical of an aliphatictetracarboxylic acid having 8 to 12 C atoms; amines from this classwhich are of particular technical interest are those of the formulae##STR30## and esters of butane-1,2,3,4-tetracarboxylic acid with 2 unitseach of 1,2,2,6,6-pentamethyl-4-hydroxy-piperidine and C₁₃ H₂₇ --OH(amine F);

compounds of the formula V in which n is 2, G and G¹ are hydrogen,

G¹¹ is hydrogen or methyl and

G¹³ is hydrogen or C₁ -C₈ alkyl, and

G¹⁴ is C₂ -C₈ alkylene or 1-oxo-C₂ -C₈ alkylene; an amine from thisclass which is of particular technical interest is the compound of theformula ##STR31##

compounds of the formula VIIC in which n is 1, G, G¹ and G¹⁷ arehydrogen,

G¹¹ is hydrogen or methyl and

T₁ and T₂ together with the C atom linking them form a C₅ -C₁₄cycloalkane ring; an amine from this class which is of particulartechnical interest is the compound of the formula ##STR32##

compounds of the formula VIII in which n is 1 or 2

G¹⁸ and G¹⁹ are a group of one of the formulae ##STR33##

G¹¹ is hydrogen or methyl,

G¹ and G² are hydrogen or together are a substituent ═O,

E is --O-- or --NG¹³ --,

A is C₂ -C₆ alkylene and

x is 0 or 1,

G¹³ is hydrogen, C₁ -C₁₂ alkyl or cyclohexyl,

G²⁰, in the case where n is 1, is identical to G¹⁸ and, in the casewhere n is 2, is a group --E--B--E--, in which B is C₂ -C₈ alkylene orC₂ -C₈ alkylene which is interrupted by 1 or 2 groups --N(G²¹)--,

G²¹ is C₁ -C₁₂ alkyl, cyclohexyl, benzyl or C₁ -C₄ hydroxyalkyl or agroup of the formula ##STR34## or G²¹ is a group of the formula##STR35##

amines from this class which are of particular technical interest arethe compound 76) [=amine J] described above and the compounds of theformulae ##STR36##

(amines K and L):

compounds of the formula X in which n is 2, G¹¹ is hydrogen or methyland G¹⁴ is C₂ -C₁₂ alkylene;

an amine from this class which is of particular technical interest isthe compound (100) [=amine M] described above; and

oligomer compounds having 2 to 10 recurring units, such as areobtainable by reaction of

(i) of ##STR37## in which G²⁴ is C₂ -C₅ hydroxyalkyl with an aliphaticC₂ -C₁₂ dicarboxylic acid or a suitable reactive derivative, such as thediester, dichloride or anhydride;

(j) of a linear oligomer polyester obtained by reaction of a dialcoholwith butane-1,2,3,4-tetracarboxylic acid with2,2,6,6-tetramethyl-4-hydroxypiperidine;

(k) of ##STR38## in which A is C₂ -C₆ alkylene, T³ is C₁ -C₁₈ alkyleneor cyclohexyl, T⁴ is hydrogen or C₁ -C₁₈ alkyl, or T³ and T⁴ togetherare C₄ -C₆ alkylene or C₃ -C₅ oxaalkylene;

(l) of H₂ N--A--NH--A--NH₂ with ##STR39## and Br--A--Br, in which A isC₂ -C₆ alkylene;

(m) of compounds of the formula ##STR40## with epichlorohydrin;

(n) of ##STR41## and those of the formula

(o) ##STR42## in which about one third of the radicals R are --C₂ H₅ andthe others are ##STR43## and m is a number from the range 2 to 10;

oligomer amines of particular technical interest include those of theformulae (m again is a number from the range 2 to 10) ##STR44## in whichabout one third of the radicals R are --C₂ H₅ and the others are##STR45##

a linear polyester having 2 to 10 recurring units obtained by reactionof butane-1,2,3,4-tetracarboxylic acid with a dialcohol of the formula##STR46## in which the end groups and side chains are formed byesterification of the free carboxylic groups with2,2,6,6-tetramethyl-4-hydroxypiperidine (amine S); a copolymer whoserecurring units are composed of 2 units ##STR47## and 1 unit each of##STR48##

the reaction product of H₂ N--(CH₂)₂ --NH--(CH₂)₂ --NH₂ with ##STR49##and Br--(CH₂)₂ --Br (amine U); and the reaction product of the compoundof the formula ##STR50## with epichlorohydrin (amine W).

The oligomer amines are often mixtures of compounds which differ fromone another with respect to their chain length.

Of particular importance is the use of the amines A, B, C, D, E, F, G,H, J, K, L, M, N, O, P, Q, R, S, T, U, V and W specified above.

In the process according to the invention, preference is given inparticular to the addition of those amines whose molecular weight oraverage molecular weight M_(n) is in the range 300 to 10,000, inparticular in the range 1000 to 10,000. Of these, those amines whosemolecular weight or average molecular weight M_(n) is in the range 1500to 10,000, for example in the range 2000 to 7500 should again bementioned in particular. The amines of higher molecular weight are inparticular sterically hindered amines.

The amines mentioned are known compounds; many of them are commerciallyavailable.

In the process according to the invention preference is given tostabilization of phosphites or phosphonites having one of the formulae(1) to (7), ##STR51## in which the indices are integers and

n' is 2, 3 or 4; p is 1 or 2; q is 2 or 3; r is 4 to 12; y is 1, 2 or 3;and z is 1 to 6;

A', in the case where n' is 2, is alkylene having 2 to 18 carbon atoms;alkylene which is interrupted by --S--, --O-- or --NR'₄ -- and has 2 to12 carbon atoms; a radical of one of the formulae ##STR52## orphenylene;

A', in the case where n' is 3, is a radical of the formula --C_(r)H_(2r-1) --;

A', in the case where n' is 4, is a radical of the formula C(CH₂)₄,

A", in the case where n' is 2, has the meaning of A';

B' is a radical of the formula --CH₂ --; --CHR'₄ --; --CR'₁ R'₄ --;--S-- or a direct bond; or is C₅ -C₇ cycloalkylidene; or iscyclohexylidene which is substituted in the 3, 4 and/or 5 position by 1to 4 C₁ -C₄ alkyl radicals;

D',in the case where p is 1, is methyl and, in the case where p is 2, is--CH₂ OCH₂ --;

E', in the case where y is 1, is alkyl having 1 to 18 carbon atoms,phenyl, a radical of the formula --OR'₁ or halogen;

E', in the case where y is 2, is a radical of the formula --O--A"--O--;

E', in the case where y is 3, is a radical of the formula R₄ 'C(CH₂ O)₃;

Q' is the radical of an at least z-valent alcohol or phenol, thisradical being attached to the P atom(s) via the alcoholic or phenolic Oatom(s);

R'₁, R'₂ and R'₃, independently of one another, are alkyl having 1 to 30carbon atoms; alkyl which is substituted by halogen, --COOR₄ ', --CN or--CONR₄ 'R₄ ' and has 1 to 18 carbon atoms; alkyl which is interruptedby --S--, --O-- or --NR'₄, and has 2 to 18 carbon atoms; phenyl-C₁ -C₄alkyl; cycloalkyl having 5 to 12 carbon atoms; phenyl or naphthyl;phenyl or naphthyl each of which is substituted by halogen, 1 to 3 alkylradicals or alkoxy radicals having a total of 1 to 18 carbon atoms or byphenyl-C₁ -C₄ alkyl; or is a radical of the formula ##STR53## in which mis an integer from the range 3 to 6;

R'₄ or the radicals R₄ ' independently of one another, are hydrogen;alkyl having 1 to 18 carbon atoms; cycloalkyl having 5 to 12 carbonatoms; or phenylalkyl having 1 to 4 carbon atoms in the alkyl moiety;

R'₅ and R'₆, independently of one another, are hydrogen; alkyl having 1to 8 carbon atoms or cycloalkyl having 5 or 6 carbon atoms;

R'₇ and R'₈, in the case where q is 2, are, independently of oneanother, C₁ -C₄ alkyl or together are a 2,3-dehydropentamethyleneradical; and

R'₇ and R'₈, in the case where q is 3, are methyl;

the substituents R'₁₄, independently of one another, are hydrogen; alkylhaving 1 to 9 carbon atoms or cyclohexyl;

the substituents R'₁₅, independently of one another, are hydrogen ormethyl; and

R'₁₆ is hydrogen or C₁ -C₄ alkyl and, in the case where several radicalsR'₁₆ are present, the radicals R'₁₆ are identical or different;

X' and Y' are each a direct bond or --O--; and

Z' is a direct bond; --CH₂ --; --C(R'₁₆)₂ -- or --S--.

Particular preference is given to a process in which the phosphite orphosphonite is one of the formulae (1), (2), (5) or (6), in which

n' is 2 and y is 1 or 2;

A' is alkylene having 2 to 18 carbon atoms; p-phenylene orp-biphenylene;

E', in the case where y is 1, is C₁ -C₁₈ alkyl, --OR₁ or fluorine; and,in the case where y is 2, is p-biphenylene;

R'₁, R'₂ and R'₃, independently of one another, are alkyl having 1 to 18carbon atoms;

phenyl-C₁ -C₄ alkyl; cyclohexyl; phenyl; phenyl which is substituted by1 to 3 alkyl radicals having a total of 1 to 18 carbon atoms;

the substituents R'₁₄, independently of one another, are hydrogen oralkyl having 1 to 9 carbon atoms;

R'₁₅ is hydrogen or methyl;

X' is a direct bond;

Y' is --O--; and

Z' is a direct bond or --CH(R'₁₆)--.

Of particular technical interest is a process for stabilizing aphosphite or phosphonite of one of the formulae (1), (2), (5) or (6), inwhich

n' is 2 and y is 1;

A' is p-biphenylene;

E' is C₁ -C₁₈ alkoxy;

R'₁, R'₂ and R'₃, independently of one another, are phenyl which issubstituted by 2 or 3 alkyl radicals having a total of 2 to 12 carbonatoms;

the substituents R'₁₄, independently of one another, are methyl ortert-butyl;

R'₁₅ is hydrogen;

X' is a direct bond;

Y' is --O--; and

Z' is a direct bond, --CH₂ -- or --CH(CH₃)--.

Particular preference is given to phosphites, in particular those of theformulae (1) and (5).

The following compounds are examples of phosphites and phosphoniteswhose stability to hydrolysis can be improved particularlyadvantageously by the process according to the invention; ##STR54##

The phosphites and phosphonites mentioned are known compounds; some ofthem are commercially available.

Some commercial phosphites and phosphonites are present as mixtures ofcompounds or in prestabilised form. In most cases, an amine, for examplea lower alkylamine or triisopropanolamine, has been admixed to thesecompounds in a conventional manner in a concentration of about 1% asprestabilization. The hydrolytic stability of such products can also besignificantly improved by the process according to the invention.

The products of the process according to the invention canadvantageously be used as stabilizers of organic material, in particularorganic polymers, for example synthetic polymers, against the damagingeffect of heat, oxygen and/or light. Examples of such polymers can beseen, for example, from U.S. Pat. No. 4,855,345, column 4, line 63, upto column 7, line 54.

The phosphites and phosphonites stabilized according to the inventionare distinguished by their excellent resistance to hydrolysis and have along shelf life even at high atmospheric humidity. An organic phosphiteor phosphonite stabilized against hydrolysis, such as obtainable by theprocess described above, is therefore also provided by this invention.

The examples which follow illustrate the process according to theinvention further. All parts or percentages given are, just as in theremaining description and in the claims, by weight, unless statedotherwise. As far as percentages are based on phosphite or phosphonite,they refer to phosphite or phosphonite in the melt unless a differentreference amount is expressly stated. The structural formulae of thephosphites, phosphonites and amines used in the examples are, if notstated directly, listed above in the text.

EXAMPLE 1

300 g of phosphite Ph-1 are brought to 70°-75° C. together with 225 g ofisopropanol, 2.25 g of toluene and 30 g of amine A(=triisopropanolamine) with stirring. The resulting homogeneous melt isadded over a period of about 1 hour with stirring to a suspension of 20g of Ph-1 in 450 g of isopropanol and 20 g of amine A whose temperatureduring this process is maintained at 20°-30° C. by cooling. The mixtureis then cooled to 10°-15° C. and stirred in this temperature range foranother 3 hours. The crystalline product is then filtered off and driedat 60° C. under reduced pressure.

Elemental analysis gives an amine A content of 1.2% by weight (relativeto phosphite) for the dry product.

A sample serving as comparison is crystallized without adding an amine.

Equal amounts of the product are then subjected to the following testsof resistance to hydrolysis:

a) During storage, the time is measured in which upon visual inspectionthe initial powder starts to deliquesce (transition p-c) and the timewhich expires until the material is liquid (transition c-l). At thelast-mentioned point in time, the weight increase during the duration ofstorage is noticed; the weight increase gives an indication of the waterabsorption of the material. The test conditions (temperature andatmospheric humidity during storage) are given in the particularexamples.

b) After 8 hours of storage at 70° C. and 100% atmospheric humidity, thephosphite Ph-1 content is determined by liquid chromatography.

The results can be seen from Table 1.

EXAMPLE 2-13

Compound Ph-1 is stabilized with amines A, C, E, H, J, K, P, Q and U bythe method described in Example 1; however, in contrast to Example 1, nophosphite and no amine are introduced into the crystallization medium atthe beginning. The product obtained is tested for resistance tohydrolysis as described in Example 1. The test conditions in test a:storage at 50° C. and 75% atmospheric humidity.

Further conditions and test results are summarized in Table 1.

In Table 1 and the following tables, the column headings have thefollowing meaning:

% intr.: amount of amine in the melt, % given is based on phosphite orphosphonite in the melt;

% cont.: amine content in the phosphite or phosphonite aftercrystallization;

Solv1, %: main solvent for the melt, % given is based on phosphite orphosphonite in the melt;

Solv2, %: further solvent for the melt, % given is based on phosphite orphosphonite in the melt;

T/°C.: temperature range of the melt or crystallization medium;

Solvent, %: solvent for crystallization medium, % given is based onphosphite or phosphonite in the melt;

IPA: isopropanol;

TOL: toluene;

MeOH: methanol;

% seed cr.: initial charge of phosphite as seed crystals, % given isbased on phosphite or phosphonite in the melt;

% amine: initial charge of amine in the crystallization medium, % givenis based on phosphite or phosphonite in the melt;

% dec. (8h): decomposition of the sample after 8 h in % (100%=phosphitecontent at the beginning of the test) [test b)];

p-c/h: time in hours until deliquescence begins [test a)];

c-l/h (% W): time in hours until sample has become liquid (clearsolution). Numbers given in brackets: weight increase of the samplecompared with the beginning of the test (% by weight is based on thebeginning of storage=water content) [test a)].

                                      TABLE 1                                     __________________________________________________________________________    Stabilization of bis(2,4-di-tert-butyl-6-methylphenyl) ethyl phosphite        (Ph-1)                                                                        MELT                          CRYST. MEDIUM    TEST RESULTS                            %  %                 Solvent,                                                                           % seed                                                                            %       % dec.                         Ex. No.                                                                            Amine                                                                             intr.                                                                            cont.                                                                            Solv1, %                                                                           Solv2, %                                                                            T/°C.                                                                      %    cr. amine                                                                             T/°C.                                                                      (8 h)                                                                              p-c/h                                                                             c-l/h (%              __________________________________________________________________________                                                            W)                    Compari-                                                                           none                                                                               0 0  IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                             85(n. 2 h)                                                                         005 37  (2.5)             son                                                                           1    A   10 1.2                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           6.7 6.7 20-30                                                                              5   056 126 (2.2)             2    A   20 2.7                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              3.2 110 171 (2.0)             3    Q   20 3.5                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              5   025 >120                  4    P    5 1.0                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                             13.4 056 144 (1.5)             5    P   10 2.7                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              3.1 160 220                   6    P   20 3.8                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              1.0 200 312 (1.1)             7    C   20 2.9                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                             15.2 040 72  (2.7)             8    J   10 1.5                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              9.5 040 72  (1.0)             9    J   20 3.1                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              2.0 135 171 (1.3)             10   H   10 6.5                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                             12.4 056 120 (1.5)             11   K   10 1.4                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                             19.4 032 48  (1.0)             12   U   10 0.9                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              4.5 056 120 (1.6)             13   E   10 0.9                                                                              IPA, 75                                                                            TOL, 0.75                                                                           70-75                                                                             IPA, 150                                                                           0   0   20-30                                                                              8.6 032 48  (0.8)             __________________________________________________________________________

EXAMPLES 14-17

A commercial phosphonite mixture containing Ph-3 as the main componentis stabilized by the method described in Examples 2-13; composition ofthe batch: ##STR55##

The stabilized mixture is tested for resistance to hydrolysis by meansof test a); test conditions: storage at 50° C. and 75% atmospherichumidity. Process conditions and test results are summarized in Table 2.

EXAMPLES 18-23

Compounds Ph-5 and Ph-6 are stabilized by the method described inExamples 2-13 and tested for resistance to hydrolysis by means of testa). Test conditions: storage at 50° C. and 75% atmospheric humidity.Test conditions and test results are summarized in Tables 3 and 4.

EXAMPLES 24-29

Compound Ph-2 is stabilized by the method described in Examples 2-13 andtested for resistance to hydrolysis by means of test a); testconditions: storage at 70° C. and 100% atmospheric humidity. Processconditions and test results are summarized in Table 5.

EXAMPLES 30-33

A commercial phosphonite mixture containing Ph-3 as the main componentis stabilized by the method described in Examples 2-13; composition ofthe batch (for formulae, see Examples 14-17):

Ph-3: 35%

Ph-2: 09%

Ph-3b: 20%

Ph-3c: 04%

Ph-3d: 15%

further compounds: 17%.

The stabilized mixture is tested for resistance to hydrolysis by meansof test a); test conditions: storage at 50° C. and 75% atmospherichumidity. Process conditions and test results are summarized in Table 6.

                                      TABLE 2                                     __________________________________________________________________________    Stabilizing of a phosphonite mixture containing the main component of the     formula                                                                        ##STR56##                                                                           MELT                                                                              %  %                CRYST. MEDIUM        TEST RESULTS               Ex. No.                                                                             Amine                                                                             intr.                                                                            cont.                                                                            Solv1, %                                                                           Solv2, %                                                                           T/°C.                                                                      Solvent, %                                                                          % seed cr.                                                                          % amine                                                                            T/°C.                                                                      p-c/h                                                                             c-l/h (%              __________________________________________________________________________                                                            W)                    Comparison                                                                           none                                                                               0 0  IPA, 300                                                                           --   60-65                                                                             MeOH, 400                                                                           0     0    15-20                                                                              110                                                                              150 (15)              14     J   20 3.4                                                                              IPA, 300                                                                           --   60-65                                                                             MeOH, 400                                                                           0     0    15-20                                                                             >360                      15     N    5 5  IPA, 300                                                                           --   60-65                                                                             MeOH, 400                                                                           0     0    15-20                                                                              260                      16     N   10 10 IPA, 300                                                                           --   60-65                                                                             MeOH, 400                                                                           0     0    15-20                                                                             >360                      17     C   20 2.8                                                                              IPA, 300                                                                           --   60-65                                                                             MeOH, 400                                                                           0     0    15-20                                                                             >360                      __________________________________________________________________________

                                      TABLE 3                                     __________________________________________________________________________    Stabilization of the compound of the formula                                   ##STR57##                                                                           MELT                                                                              %  %                CRYST. MEDIUM        TEST RESULTS              Ex. No.                                                                              Amine                                                                             intr.                                                                            cont.                                                                            Solv1, %                                                                           Solv2, %                                                                           T/°C.                                                                      Solvent, %                                                                          % seed cr.                                                                          % amine                                                                            T/°C.                                                                      p-c/h                                                                             c-l/h (%              __________________________________________________________________________                                                            W)                    Comparison                                                                           none                                                                               0 0  TOL, 250                                                                           --   75-80                                                                             MeOH, 500                                                                           0     0    20-25                                                                              5  17 (30)               18     A   20 0.5                                                                              TOL, 250                                                                           --   75-80                                                                             MeOH, 500                                                                           0     0    20-25                                                                              8  24 (33)               19     P   20 2.0                                                                              TOL, 250                                                                           --   75-80                                                                             MeOH, 500                                                                           0     0    20-25                                                                              8  24 (24)               20     N   10 4.8                                                                              TOL, 250                                                                           --   75-80                                                                             MeOH, 500                                                                           0     0    20-25                                                                             15  48 (37)               21     N   20 10.5                                                                             TOL, 250                                                                           --   75-80                                                                             MeOH, 500                                                                           0     0    20-25                                                                             15  48                    __________________________________________________________________________                                                            (28)              

                                      TABLE 4                                     __________________________________________________________________________    Stabilization of the compound of the formula                                   ##STR58##                                                                           MELT                                                                              %  %                CRYST. MEDIUM        TEST RESULTS              Ex. No.                                                                              Amine                                                                             intr.                                                                            cont.                                                                            Solv1, %                                                                           Solv2, %                                                                           T/°C.                                                                      Solvent, %                                                                          % seed cr.                                                                          % amine                                                                            T/°C.                                                                      p-c/h                                                                             c-l/h (%              __________________________________________________________________________                                                            W)                    Comp.  none                                                                               0 0  TOL, 500                                                                           IPA, 50                                                                            75-80                                                                             IPA, 500                                                                            0     0    15-20                                                                               96                                                                              168 (30)              22     A   20 1.1                                                                              TOL, 500                                                                           IPA, 50                                                                            75-80                                                                             IPA, 500                                                                            0     0    15-20                                                                             >400                      23     N   20 2.0                                                                              TOL, 500                                                                           IPA, 50                                                                            75-80                                                                             IPA, 500                                                                            0     0    15-20                                                                              210                                                                              240                   __________________________________________________________________________

                                      TABLE 5                                     __________________________________________________________________________    Stabilization of tris(2,4,-di-tert-butylphenyl) phosphite (Ph-2)                     MELT                    CRYST. MEDIUM                                             %  %                            %       TEST RESULTS               Ex. No.                                                                              Amine                                                                             intr.                                                                            cont.                                                                            Solv1, %                                                                           Solv2, %                                                                           T/°C.                                                                      Solvent, %                                                                          % seed cr.                                                                          amine                                                                             T/°C.                                                                      p-c/h                                                                              c-l/h (%              __________________________________________________________________________                                                            W)                    Comparison                                                                           none                                                                              0  0  TOL, 200                                                                           --   75  IPA, 600                                                                            0     0   20-30                                                                             026  47  (27)              24     N   2  0.7                                                                              TOL, 200                                                                           --   75  IPA, 600                                                                            0     0   20-30                                                                             216  240 (11)              25     N   5  1.8                                                                              TOL, 200                                                                           --   75  IPA, 600                                                                            0     0   20-30                                                                             216  240 (11)              26     N   10 5.1                                                                              TOL, 200                                                                           --   75  IPA, 600                                                                            0     0   20-30                                                                             240  312 (16)              27     N   25 16.1                                                                             TOL, 200                                                                           --   75  IPA, 600                                                                            0     0   20-30                                                                             >312 >312                                                                              (0)               28     P   2  0.1                                                                              TOL, 200                                                                           --   75  IPA, 600                                                                            0     0   20-30                                                                             192  216                   29     P   5  3.8                                                                              TOL, 200                                                                           --   75  IPA, 600                                                                            0     0   20-30                                                                             216  240                   __________________________________________________________________________

                                      TABLE 6                                     __________________________________________________________________________    Stabilization of a phosphonite mixture containing the main component of       the formula                                                                    ##STR59##                                                                           MELT                   CRYST. MEDIUM        TEST RESULTS               Ex. No.                                                                              Amine                                                                             % intr.                                                                           % cont.                                                                            Solvent, %                                                                          T/°C.                                                                      Solvent, %                                                                          % seed cr.                                                                          % amine                                                                            T/°C.                                                                      p-c/h                                                                             c-l/h (%               __________________________________________________________________________                                                           W)                     Comparison                                                                           none                                                                               0  0    IPA, 400                                                                            75  MeOH, 400                                                                           0     0    20-30                                                                              24  48 (3.4)              30     N    5  7.5  IPA, 400                                                                            75  MeOH, 400                                                                           0     0    20-30                                                                             348 360 (0.2)              31     N   10  18.2 IPA, 400                                                                            75  MeOH, 400                                                                           0     0    20-30                                                                             504 816 (2.2)              32     N   25  32.3 IPA, 400                                                                            75  MeOH, 400                                                                           0     0    20-30                                                                             648 840 (0.9)              33     P    2  2.1  IPA, 400                                                                            75  MeOH, 400                                                                           0     0    20-30                                                                             240 312                    __________________________________________________________________________                                                           (2.6)              

EXAMPLE 34-35

Compound Ph-5 is stabilized by the method described in Examples 2-13.The crystallization medium used is isopropanol without any furtheraddition. The unstabilized and stabilized compound are tested forresistance to hydrolysis by means of test a). Test conditions: storageat 50° C. and 75% atmospheric humidity. Further process conditions andtest result (c-l/h=time in hours until sample becomes deliquescent) aresummarized in Table 7.

                                      TABLE 7                                     __________________________________________________________________________    Stabilization of the compound of the formula                                   ##STR60##                                                                    MELT                   CRYST. MEDIUM RESULTS                                  Ex. No.                                                                            Amine                                                                             % intr.                                                                           % cont.                                                                            Solv., %                                                                           T/°C.                                                                      Solv., %                                                                           T/°C.                                                                      c-l/h                                     __________________________________________________________________________    Comp.                                                                              none                                                                              0   0    TOL, 250                                                                           75  IPA, 600                                                                           20-30                                                                              8                                        34   N   5   1.3  TOL, 250                                                                           75  IPA, 600                                                                           20-30                                                                             24                                        35   P   5   0.15 TOL, 200                                                                           75  IPA, 600                                                                           20-30                                                                             24                                        __________________________________________________________________________

The examples show that the phosphites prepared and stabilized accordingto the invention exhibit much better resistance to hydrolysis in moistair than unstabilized phosphites.

What is claimed is:
 1. A process for stabilizing a crystalline organicphosphonite or phoshonite against hydrolysis, which comprisesintroducing a mixture comprising phosphite or phosphonite, a solvent ora solvent mixture, and 0.1 to 100% by weight (relative to phosphite orphosphonite) of an amine and having a temperature of 50°-100° C. as ahomogeneous melt into a liquid crystallization medium whose temperatureduring the addition is maintained 10°-70° C. below the temperature ofthe melt.
 2. Process according to claim 1, in which the melt comprisesan alcohol or a hydrocarbon in an amount of 20 to 500% by weight,relative to the phosphite or phosphonite, as the main solvent and afurther solvent in an amount of 0-50% by weight, relative to the mainsolvent.
 3. A process according to claim 1, in which the temperature ofthe melt is 55°-90° C.
 4. A process according to claim 1, in which thedifference in temperature between melt and crystallization medium is30°-70° C.
 5. A process according to claim 1, in which thecrystallization medium is maintained at a temperature which is at least10° C. below the resulting temperature of the liquid.
 6. A processaccording to claim 1, in which 80-800% by weight (relative to thephosphite or phosphonite) of a solvent are used as the crystallizationmedium.
 7. A process according to claim 6, in which a C₁ -C₅ alkanol ora mixture of various C₁ -C₅ alkanols is used as the crystallizationmedium.
 8. A process according to claim 6, in which the crystallizationmedium consists of a suspension of 2 to 20% by weight of crystallinephosphite or phosphonite, relative to the phosphite or phosphonite inthe melt.
 9. A process according to claim 1, in which thecrystallization medium is saturated with 50-100% of amine.
 10. A processaccording to claim 1, in which the melt contains 0.1 to 50% by weight ofamine (relative to the phosphite or phosphonite).
 11. A processaccording to claim 1, in which the amine used is one of the formula I##STR61## in which X¹ and X², independently of one another, are H, C₁-C₂₀ alkyl, C₄ -C₂₀ alkyl which is interrupted by one or more --O-- andunsubstituted or substituted by one or more hydroxyl groups, or is C₂-C₂₀ hydroxyalkyl, and X³ is C₂ -C₂₀ alkyl, C₄ -C₂₀ alkyl which isinterrupted by one or more --O-- and unsubstituted or substituted by oneor more hydroxyl groups, or is --(CH₂)_(m) --NX¹ X², or C₂ -C₂₀hydroxyalkyl, or in which X² and X³ together are --(CH₂)_(m) --, --C₂ H₄--O--C₂ H₄ -- or --C₂ H₄ --NX¹ --C₂ H₄ --, m being an integer from therange 4 to 6 and X¹ and X² being as defined above; or a cyclicsterically hindered amine containing at least one group of the formulaeII or III ##STR62## in which G is hydrogen or methyl, and G₁ and G₂ arehydrogen, methyl or together are ═O.
 12. A process according to claim10, in which the amine used is a tertiary amine of the formula I or acyclic sterically hindered amine containing at least one group of theformulae II or III, in which G is hydrogen and G¹ and G² are hydrogen ortogether are a substituent ═O.